Adaptable electric hand tool



March 23, 1937.

H. A. UNGAR ADAPTABLE ELECTRIC HAND TOOL Filed June 26, 1935 /az/a Patented Man 23, 1937 i UNITED STATES PATE-NT oFFlcE 3 Claims.

` This invention is an electric hand tool of the type embodying a soldering-iron element.

' An object of the invention is to provide a tool of this class with means to greatly increase its 5 utility by theready interchange of various tip elementsfor performing several kdifferent functions as-met in divers arts and professions as later disclosed herein.

A further object', is to provide an implement of this type of rugged and substantial structure, and

at the same time of low cost and of a highly practical combination.

I'he invention consists of certain advancements in this art as set forth in the ensuing disclosure and having, with `the above, additional objects and4 advantages as hereinafter developed, and whose construction, combinations and details of means, and the manner of operation and the mode of manufacture will be made manifest in the description of the herewith illustrative em bod1ment; it being understood that modifications, Variations and adaptations may be resorted to u within the scope, principle and spirit of the invvention as it is more directly claimed hereinbelow.

i It is understood that the functional use of the apparatus of this disclosure in any other art than that herein set forth is deemed to be within the adaptation of the invention. .Y

Figure 1 is a side elevation, slightly broken away, of the tool as adapted for hot point scribing. Figure 2 is a perspective of a flexible blade element applicable to the tool. Figure 3 is a perspective of al dental-wax applying element for the tool. Figure .4 is a side elevation of an adapt- 5 able element fory soldering. Figure 5 is a sectional, side elevation of the handle of the tool, and Figure 6 is an end view thereof. Figure 7 is a side elevation of the'heating unit assembly of the tool. Figure 8 is a side elevation of the unit muzzle, and Figure 9 is an end view thereof.

Figure 10 is a side elevation of the high voltage, l

The tool includes a hard, di-electric, *tubular handle 2 of hollow conical formA diverging fromV its remote end toward a transverse, peripheralnange 3 on its larger end and which flange serves as a means to elevate its end of the handle from a plane support on which it vmay rest and as a heat barrier to protect the fingers of the user of the tool who grips the handle just. back of the guard-flange 3. As a further protection against such heat as may be conducted back by the hanis wide-space coiled at I5b back toward theop- -posite end of the tube I3, stopping at about its dle 2 this is provided with a cushion sleeve l, preferably of cork or cork composition, snug fitting the large end of the handle.

Extending into the handle is an electric serv- I ice cord 5 whose wires 6--1 are knotted at 8 5 and pulled back and jammed tightly in the bore of the handle so that any twisting` effort formed in the extension cord during its use will not be transmitted to parts attached to the ends of the wires in the handle; that is to the heating unit 10 assembly of the tool.

The assembly, as shown in Fig. 7`, includes a ceramic bushing I0 with'a reduced end II adapted to be pushed into and cemented in the flanged end of the handle 2 and fixed therein by a key, of any suitably type, I2, A feature of the assembly resides in means for providing for adaptation of one or another of various working elements of which a set is provided with the present device, and providing for use of the tool as a burning scriber'without attachment of an extra pieceA or working element.

Extending through the bushing I0 is a small, ceramic tube I3, Fig. 10, through which extends a small `ribbon-Wire conductor I4. A highly effective method o f making up the heating coil unit of the tool resides in wrapping a fine, la-Y ment wire I5 about the extended end I llfv of the ribbon I4, Fig. 1l, and then bendingthe end I4a back over the end of the tube I3 and then making a few turns of the lament I5 on the lapped end to tie it down on the tube. Then the filament is coiled at I5a to form the hot zone of the unit (when energized) and from this coil the lament mid-length where it is wrapped at I5c on a lap` of ribbon wire IB on the tube.

' All of the coiled filament I5 is now coated with a plastic, cement insulator I'I, Fig. 7, and when 40 the coat has set, or before if preferred, it is passed into the bore of the tube and cemented in position so that the hot zone coils I5E will project enough to receive a metal muzzle I8 which teley scopes over the insulated filament I5; the muzzle 45 being worked into the outer end of the bushing I0 at the same time that the filament and its core tube is being inserted and cemented in the bushing. When `the heater assembly has set one ribbon wire, as I6, is electrically attached to a con- 50 ductor as 1, Fig. 7, and the other ribbon I4 is attached to the conductor 6. But before the latter connection is made a'glass or, ceramic tubular shield I9 is threaded on the conductor wire 6. Then when the wire 6 is connected to the ribbon 55 1.0 in the tapered bore of the handle and at which. instant the bushing In will be brought into con' tiguity with the larger end of the handle, wherein it will then be cemented and keyed to complete the tool structure.

'I'he muzzle I8 is shown as having a laterally directed scribing nib I8* for use on various materials without heat, but if a burning tool is desired then the heating unit in the muzzle I8 is energized by electric current. For the purpose of enabling the use of the tool for various kinds of work the muzzle is providedV for reception of complementary working elements. In Fig. 2 there is shown a thin bladed element 20 having a chambered hub 2| to screw onto the threads I 8b of the muzzle and thus telescope over the scribing nib. 'Ihe hub 2| has a drain hole 22 for escape of a finishing wax or uid onto the blade when-this is heated by the energized unit in themuzzle. Fig. 3 illustrates a form of dental wax applyingand working element 23, with a chambered and draining hub 24 attachable to the muzzle I8. In Fig.` 4 is shown a soldering iron or block 25 attachable -to the muzzle I8, as desired. Where necessary to retard ilow of the heated wax or fluid/in the tool hubs it is obvious that a wick may be introduced with that object.

In Fig. 12 there is disclosed a form of heating unit especially designed for utilization of lcw .40 voltage current as when derived vfor a battery as source of supply. In this. unit the ribbon-wire Il* is helically coiled at 21 beyond theend of the tube I8- andl is joined directly to the muzzle I8 to the opposite end of which isl attached a' con- 45 ductor.

The knot 8 in the wires of the service cord is not only a strain release for the terminals of the heating unit but also is a stop, when e the tapered bore of the handle, against the outward pull of the cord in the handle.

The terminals of the unit are attached to the wires 8-1 by lapping a terminal of the ribbon Il on one wire and twisting them together and then clinching them in an applied sheath lIl', Fig. 7.

What is claimed is: l

1. An electric hand tool including a heating coll assembly whichv includes a bushing and a core tube extending from one end thereof, a resistance coil cemented on the tube andin the bushing, coil terminals one of which extends through the tube and the other free outside thereof, service wires connected to the' terminals and a refractory tubular shield telescoped oriy one of the connections and telescoping over the extended core end.

2. An electric hand tool including a heating coil assembly comprising a refractory core tube, a iilament coiled on one end thereof, wires -oi which one extends through the. tube and has one end lapped on one end of the tube and bound by one end of the filament and the'other wire being attached to the other end of this filament`` Y on the tube, a coat of insulating cement covering the coiled iilament, a bushing in which the coated coil and tube is cemented and from which the tube extends at each end, and a muzzle xed on the endof the tube having the filament coil and also xedin the bushing.

3. An electric heating' unit including a' working muzzle, a refractory core tube terminating in the muzzle, a wire extending through the tube, a resistance coll, and service connections with and for current through the wire and coil; said tube being cemented in the muzzle; said coil formed of a ilament wrapped close on one end of the tube and wide space wrapped medially along the y tube so as to form a hot zone entirely within the mumle.

HARRY A. UNGAR. 

